DEVELOPMENT OF OXIDATION CATALYSTS UTILIZING CHARACTERISTICS OF HETEROPOLY COMPOUNDS

1. 合成了单、二、三铁取代多金属氧酸盐并对其进行了表征。过氧化氢的利用效率和活性在很大程度上取决于铁中心，二铁取代的多金属氧酸γ - siw_ <10>{Fe(0H_2)}_20_<38>^<6->对过氧化氢的利用和转化效率最高。dr-铁取代多金属氧酸盐催化环己烷的氧化反应，过氧化氢对氧化产物的利用效率可达100%左右。如此高的效率从未有过报道。除环己烷外，还催化氧化了正己烷、正戊烷和金刚烷，过氧化氢利用率高。用γ - siw_ <10>{Fe(OH_2)}_2O_<38>^<6->将甲烷氧化为甲醇。还表明，在使用的条件下和过氧化氢存在下，二铁取代的多金属氧酸盐是稳定的。发现keggin型异多酸盐具有分子氧选择性氧化异丁烷的催化作用。Cs和V的最佳含量分别为2.5和1，Ni的加入增强了异丁烷氧化的催化活性。优选的Ni含量为0.08。结果表明，异丁烷氧化是一种表面型反应，催化活性受催化剂表面氧化能力的控制。cs2.5 ni0.08 h1.34 pvmo11o40o也能催化丙烷的氧化。

1. Mono-, di-, and tri-iron-substituted polyoxometalates were synthesized andcharacterized. The efficiency and activity for the utilization of hydrogen peroxide greatly depended on the iron centers and the di-iron-substituted polyoxometalate, gamma-SiW_<10>{Fe(0H_2)}_20_<38>^<6->, showed the highest efficiency of hydrogen peroxide utilization and conversion based on substrates used. It is remarkable that the efficiency of hydrogen peroxide utilization to oxygenated products reached up to ca. 100% for the oxygenation of cyclohexane catalyzed by dr-iron-substituted polyoxometalate. Such a high efficiency has never been reported. Not only cyclohexane but also n-hexane, n-pentane, and adamantane were catalytically oxygenated with high efficiency of hydrogen peroxide utilization.Methane was also oxygenated to methanol by using gamma-SiW_<10>{Fe(OH_2)}_2O_<38>^<6->. It was also suggested that di-iron-substituted polyoxometalate was stable under the conditions used and in the presence of hydrogen peroxide.2. Keggin-type heteropolymolybdates have been found to catalyze the selective oxidation of isobutane with molecular oxygen. The preferable contents of Cs and V are 2.5 and 1, respectively, and the addition of Ni enhanced the catalytic activity for the oxidation of isobutane. The preferred content of Ni was 0.08. It was shown that isobutane oxidation is a surface-type reaction and the catalytic activity is controlled by the oxidizing ability of the catalyst surface. Cs2.5Ni0.08H1.34PVMo11O4O also catalyzed the oxidation of propane.